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A priest was fatally shot at a Catholic church and another was left critically injured on Wednesday, police in Phoenix said. Officers found the victims while responding to reports of a burglary around 9 p.m. local time at the Mother of Mercy Mission.

'Career Criminal' Charged in Killing of Phoenix Priest: Police

The man who was arrested for the murder of a Phoenix priest last week was described by authorities as a “career criminal” and “violent felony offender” who had only recently been released from prison.

The motive of the suspect, Gary Moran, 54, was simple, said Phoenix Police Chief Daniel Garcia during a news conference.

“We believe the motive is a crime of opportunity,” he said.

Last Wednesday, a struggle ensued after Moran tried breaking into the Mother of Mercy Mission in downtown Phoenix, Garcia said.

Father Kenneth Walker, 28, was shot to death, and a second priest, Joseph Terra, was critically injured.

Moran was arrested Sunday night at a Phoenix halfway house and charged with first-degree murder, armed robbery and other crimes. Since his release from prison in April, he had been drifting between a homeless shelter and living on the streets, Garcia said.

“He immediately went back to business,” Garcia said, adding that Moran’s criminal history included a 2005 burglary where he threatened a homeowner with a knife.

Garcia said that a “silent witness” and expedited DNA evidence analysis led to Moran's speedy arrest.

During the interrogation, Moran didn’t discuss the details of the alleged murder, Garcia said. But before he invoked his right to remain silent, Garcia added, Moran “made admissions” about the struggle.

Maricopa County Sheriff

Maricopa County Sheriff Report Gary Michael Moran as the individual arrested in the killing of Arizona priest, Kenneth Walker.

Walker was ordained in 2012, and a colleague at the Priestly Fraternity of St. Peter described him as “young” and “outgoing.” He had only recently come to Phoenix, said Mayor Greg Stanton at the news conference.